KR20160051171A - Dry Hollow Fiber Membrane, Preparation Method Thereof and Water Treatment Module Comprising The Same - Google Patents

Abstract

The present invention relates to a dry hollow fiber membrane, a method for preparing the dry hollow fiber membrane, and a water treatment module comprising the dry hollow fiber membrane. The water treatment module according to the present invention uses a dry hollow fiber membrane in which an electrostatic voltage of a surface thereof is equal to or lower than 3 kV. According to the present invention, effects are achieved in that a filling factor of the dry hollow fiber membrane is increased by minimizing the quantity of residues, and thus the time required to manufacture the hollow fiber membrane module is shortened, thereby improving workability and manufacturing efficiency.

Description

[0001] The present invention relates to a dry hollow fiber membrane, a manufacturing method thereof, and a water treatment module including the membrane hollow fiber membrane,

The present invention relates to a dry hollow fiber membrane, a method for manufacturing the hollow hollow fiber membrane, and a water treatment module including the same.

Membrane separation technology is a highly separation technology that can almost completely separate the materials to be treated present in the treated water according to the pore size of the membrane and the surface charge of the membrane. It produces high quality drinking water and industrial water in the water treatment field, And the clean production process related to the development of the zero circulation system is gradually expanding and is becoming one of the core technologies that will be attracted attention in the 21st century.

However, in order for the water treatment membrane to have commercial properties, the water permeability and the durability must be higher than the above. If the water permeability is low, the productivity of the filtrate water becomes a problem. If the durability is weak, the water treatment membrane is frequently replaced. Conventional water treatment membranes have been tried to avoid or improve the above problems by introducing various additives or hydrophilization through surface modification. However, hydrophilic additives such as polyvinylpyrrolidone and polyethylene glycol, which are commonly used hydrophilic polymers, can increase the permeability due to the improvement of hydrophilicity, but if they are not washed cleanly after the preparation, they remain in the membrane and degrade durability Factor.

In addition, since the conventional dry water treatment membrane is liable to generate static electricity on the surface, there is a problem that workability is delayed due to dust and foreign matter adherence in the air during the operation and the operation time is delayed during the manufacture of the module. In addition, there is a drawback in that the degree of integration of the separator due to static electricity is reduced and the filling rate can not be maximized. Therefore, there is a need to develop a method for solving the above-mentioned conventional durability deterioration and lowering of workability due to the generation of static electricity and lowering of the filling rate.

Korean Patent Publication No. 10-2013-0078824

The present invention provides a dry hollow fiber membrane having excellent water permeability and little generation of static electricity, a method for manufacturing the dry hollow fiber membrane, and a water treatment module including the same.

In the dry hollow fiber membrane according to one embodiment of the present invention,

A hollow structure having an outer surface layer and an inner surface layer,

And the electrostatic voltage is 3 kV or less.

A method of manufacturing a dry hollow fiber membrane according to an embodiment of the present invention includes:

Radiating a hollow fiber membrane;

Washing the radiated hollow fiber membrane;

Drying the washed hollow fiber membrane; And

And conditioning the dried hollow fiber membrane,

Wherein the conditioning step is performed at a temperature in the range of 15 to 40 DEG C and a humidity condition of 25 to 45%

And a moisture content of 1 to 3% as measured by a Karl Fischer method of the hollow fiber membrane produced.

A water treatment module according to an embodiment of the present invention includes:

A hollow fiber membrane module including the dry hollow fiber membrane;

A housing into which the hollow fiber membrane module is inserted;

An inlet formed at one side of the housing and through which the treated water flows; And

And an outlet formed at one side of the housing and through which the filtered water is discharged.

The water treatment module according to the present invention minimizes the amount of residual material by using the dry hollow fiber membrane having an electrostatic voltage of 3 kV or less to increase the filling rate of the dry hollow fiber membrane and shorten the manufacturing time of the hollow fiber membrane module, The productivity is improved.

1 is a photograph of a potting module of a water treatment module according to a comparative example.

The term "dry hollow fiber membrane" in the present invention means a hollow fiber membrane produced through a manufacturing step such as washing, drying and conditioning by spinning a hollow fiber membrane. That is, it means a state before being used for water treatment fixed in the water treatment module. Herein, "dry" means a state of a hollow fiber membrane before being used for water treatment, and is not used to exclude a wet hollow fiber membrane after being used for water treatment.

In the present invention, the term "water permeability" means a value obtained by measuring the amount of ultrapure water that has passed through a certain pressure on a unit area.

The term "asymmetric structure" in the present invention means an average size variation value of pores formed in the direction of the outer surface layer and the inner surface layer, respectively, with reference to a midpoint between an arbitrary point of the inner surface layer of the hollow fiber membrane and a corresponding point of the outer surface layer It means different.

In the present invention, "weight part" means weight ratio between each component.

In the present invention, the term " length of the dry hollow fiber membrane "refers to the direction of the long axis of the dry hollow fiber membrane, for example, the axial direction in which the dry hollow fiber membrane is radiated.

The term "vertical" in the present invention includes not only 90 degrees but also substantially 90 degrees in the mathematical sense. In the present invention, the term " vertical "

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry hollow fiber membrane, a method of manufacturing the same, and a water treatment module including the dry hollow fiber membrane,

A hollow structure having an outer surface layer and an inner surface layer,

It is possible to provide a dry hollow fiber membrane having an electrostatic voltage of 3 kV or less in the surface layer.

The dry hollow fiber membrane according to the present invention is a hollow hollow fiber filter having an outer surface layer and an inner surface layer on which pores are formed. Here, the sizes of pores formed in the outer surface layer and the inner surface layer may be different from each other. Specifically, it can have an asymmetric structure in which the pore size increases from the outer surface layer to the inner surface layer. By having such an asymmetric structure of the pores, high mechanical strength and excellent water permeability can be simultaneously realized.

At this time, the electrostatic voltage of the surface layer of the dry hollow fiber membrane may be 3 kV or less. For example, the electrostatic voltage of the dry hollow fiber membrane may range from 0.1 to 3 kV, from 0 to 3 kV, from 0 to 2 kV, or from 0 to 1 kV. The dry hollow fiber membrane having the electrostatic voltage within the above range minimizes the adherence of dust and foreign matter in the air, thereby minimizing the amount of the residual material, thereby increasing the filling rate of the dry hollow fiber membrane and decreasing the breakage rate in manufacturing the water treatment module, The manufacturing time of the hollow fiber membrane module is shortened, and workability and productivity can be improved.

The dry hollow fiber membrane may have a moisture content of 1 to 3% as measured by Karl Fischer method. Specifically, the Karl Fischer method is a method of selectively measuring only the water content in a gas, liquid, or solid sample based on chemical reaction, and is measured by a constant voltage polarization voltammetry method using a Fischer titration apparatus. For example, it can be measured using a Moisture meter CA-06 device from Mitsubishi. As an example of the measurement method, distilled water is precisely weighed out to 10 μl, and the amount of water (mg) per ml of Karl Fischer's reagent is calculated based on the reagent amount required for removing the distilled water. Then, the measurement sample is precisely measured in the range of 100 to 200 mg, and sufficiently dispersed in the measurement flask. After the dispersion, the measurement was started, the appropriate amount (ml) of the Karl Fischer reagent required for titration was accumulated, and the water content and water content were calculated by the following equations (1) and (2).

[Equation 1]

Water content (mg) = Reagent consumption (ml) × Reagent titer (mg / ml)

&Quot; (2) "

Water content (%) = [Water content (mg) / Tissue (mg)] × 100

At this time, the water content of the dry hollow fiber membrane may be 1 to 3%, 1 to 2.5% or 1 to 2%. By controlling the moisture content of the dry hollow fiber membrane within the above range, it is possible to prevent the generation of static electricity in the dry hollow fiber membrane, minimize the occurrence of bubbles in the potting part when potting the water treatment module, thereby reducing the breakage rate of the dry hollow fiber membrane, The manufacturing time of the desert module is shortened, and workability and productivity can be improved.

The dry hollow fiber membrane may have a water permeability of 1000 to 5000 LMH for ultra pure water.

Specifically, when the water permeability of ultrapure water according to the KS K 3100 condition is measured for the dry hollow fiber membrane according to the present invention, the dry hollow fiber membrane has a flow rate of 1000 to 4500 LMH, 2000 to 4000 LMH or 1000 to 3000 LMH Can be implemented.

The dry hollow fiber membrane according to the present invention may include at least one selected from the group consisting of polysulfone, polyethersulfone, and polyvinylidene fluoride as the matrix resin. The dry hollow fiber membrane according to the present invention is advantageous in that it has excellent heat resistance, has a wide pH range to be applied, and is excellent in solubility in solvents, thereby facilitating the liquid preparation of the spinning dope by using the matrix resin.

The method for producing the dry hollow fiber membrane is not particularly limited, but may include, for example, a spinning step of spinning a spinning stock solution containing a matrix resin and an inner coagulating solution through a double nozzle; A phase change step in which the spinning liquid and the inner coagulating liquid radiated from the nozzle undergo crystallization of the resin through the air gap and phase transformation with water vapor; And a pore-forming step in which the solvent and the pore-forming resin form a pore by performing phase conversion with the non-solvent.

Since the dry hollow fiber membrane according to the present invention is excellent in durability and water permeability, it can be suitably used for microfiltration, ultrafiltration or nanofiltration water treatment, and can be applied to industrial water treatment such as purified water, heavy water and sewage, . ≪ / RTI >

In addition, the present invention can provide the above-described method for producing a dry hollow fiber membrane. As one example of the method for producing the dry hollow fiber membrane,

Radiating a hollow fiber membrane;

Washing the radiated hollow fiber membrane;

Drying the washed hollow fiber membrane; And

And conditioning the dried hollow fiber membrane,

Wherein the conditioning step is performed at a temperature in the range of 15 to 40 DEG C and a humidity condition of 25 to 45%

A method of producing a dry hollow fiber membrane having a moisture content of 1 to 3% as measured by Karl Fischer method of the hollow fiber membrane produced can be provided.

The step of washing the radiated hollow fiber membrane comprises:

A horizontal flushing step of flushing the dry hollow fiber membrane using a washing water in a state where an angle formed between the longitudinal axis of the dry hollow fiber membrane and the ground surface is 30 ° or less; And

And a vertical flushing step of flushing the flame using the flushing water while the longitudinal axis of the dry hollow fiber membrane is positioned at an angle of 45 ° or more with respect to the ground.

Specifically, the water treatment module manufactured through the horizontal washing step, the vertical washing step, the normal temperature drying step, the high temperature drying step and the conditioning step under the above conditions minimizes the impurities remaining in the dry hollow fiber membrane, It is possible to prevent breakage of the dry hollow fiber membrane and to realize excellent filling rate of the dry hollow fiber membrane.

For example, the horizontal washing may be performed in a state where the angle formed by the longitudinal axis of the dry hollow fiber membrane and the paper surface is equal to or less than 30 degrees. The angle formed by the longitudinal axis of the dry hollow fiber membrane Specifically, the smallest angle between the longitudinal axis of the dry hollow fiber membrane and the ground, and the smallest angle may be horizontal.

Here, the 'angle formed by the longitudinal axis of the dry hollow fiber membrane with the ground' means an average value of the angle formed by the tangent line at the center line in the longitudinal direction of the dry hollow fiber membrane with the ground surface.

The horizontal washing may include washing with a washing water having a temperature ranging from 50 to 90 DEG C or 60 to 80 DEG C for 9 to 15 hours. In the case of flushing with the high-temperature washing water within the above-mentioned range for the time in the above range in the horizontal washing step, the impurities present on the inner and outer surfaces can be easily removed without damaging the dry hollow fiber membrane.

The angle formed by the longitudinal axis of the dry hollow fiber membrane with the ground surface in the vertical water washing step may be the smallest angle between the longitudinal axis of the dry hollow fiber membrane and the ground surface. Therefore, the vertical water washing step of the present invention may include a step of washing the dry hollow fiber membrane in a state where an angle formed by the longitudinal axis of the dry hollow fiber membrane with the ground surface is 45 ° or more.

The vertical water washing step may include washing water by supplying washing water to the longitudinal axis of the dry hollow fiber membrane. Specifically, when the washing water for washing the dry hollow fiber membrane is supplied in the longitudinal direction of the dry hollow fiber membrane and is washed with water, the inner surface and the outer surface of the dry hollow fiber membrane can easily be washed with water, It is possible.

In this case, the step of applying pressure to the washing water supplied along the longitudinal axis of the dry hollow fiber membrane and the step of not applying pressure may be repeatedly performed at the step of supplying the washing water and washing with water. Specifically, the process of applying pressure is meant to include pressing a pressure higher than the atmospheric pressure, and may be, for example, a pressure of 1.5 atm or higher or 1.5 to 10 atm. In addition, the process of not applying pressure includes a process of applying a relatively low pressure or removing the applied pressure rather than a process of applying pressure, for example, a pressure condition of 0.5 to 2 atm or 1 atm or less, And may include a vacuum state. When the process of applying the pressure in the above range and the process of applying no pressure are repeatedly performed, it becomes easier to wash and remove impurities strongly adhering to the surface and the outer surface of the dry hollow fiber membrane.

In some cases, the vertical water washing step may include a first vertical water washing step of washing with a washing water in a temperature range of 50 to 90 캜; And a second vertical water washing step of washing with rinsing water in a temperature range of 15 to 40 캜.

The first washing may include 1 to 10 minutes, and the second washing may include 1 to 20 minutes.

Specifically, the temperature range for performing the first vertical water washing step may be in the range of 50 to 90 캜 or 60 to 80 캜. In addition, the temperature range for performing the second vertical water washing step may be room temperature, specifically, 15 to 40 ° C or 20 to 30 ° C. It is possible to provide a water treatment module in which impurities on the surface and the outer surface of the dry hollow fiber membrane are efficiently provided by controlling the temperature difference in the washing step, thereby improving the water permeability and durability.

The horizontal washing step and the vertical washing step may include a step of mixing and washing the bubbles together with the washing water. The air bubble is mixed with the washing water in the horizontal washing step and the vertical washing step, thereby improving the washing power of the dry hollow fiber membrane and effectively acting to remove impurities.

In the water treatment module manufacturing process according to the present invention, impurities such as hydrophilic polymer remaining on the surface of the dry hollow fiber membrane, organic solvent contained in the solvent, and solvent can be effectively removed by performing the horizontal water washing step and the vertical water washing step.

In addition, the step of drying the washed hollow fiber membrane may include:

A normal-temperature drying step of drying at a room temperature ranging from 15 to 40 캜; And

And a high-temperature drying step of drying at a high temperature ranging from 50 to 90 占 폚.

Specifically, the temperature range for performing the normal-temperature drying step may be specifically in the range of 15 to 40 ° C or 20 to 30 ° C. Through the drying step at room temperature, the impurities remaining in the dry hollow fiber membrane can be desorbed together with water.

The temperature range for carrying out the high temperature drying step may be specifically in the range of 50 to 90 ° C or 60 to 80 ° C. Through the high temperature drying step, moisture remaining in the dry hollow fiber membrane can be completely dried.

By controlling the water content of the dry hollow fiber membrane to 1 to 3% while passing through the room temperature drying step and the high temperature drying step, the generation of static electricity in the dry hollow fiber membrane can be prevented. Thus, impurities on the surface and the outer surface of the dry hollow fiber membrane can be effectively removed, thereby providing a water treatment module with improved water permeability and durability.

When the dry hollow fiber membrane is dried in the low temperature drying step and the high temperature drying step in a state where the angle formed between the longitudinal axis of the dry hollow fiber membrane and the ground surface is 45 ° or more, It is possible to effectively prevent the dry hollow fiber membrane from being broken by securing a space in the housing and effectively increase the dry hollow fiber membrane fill factor.

The thus dried water treatment module can be stored in a dry room at about 60 to 80 ° C.

In addition, the conditioning step can control the electrostatic voltage of the dry hollow fiber membrane surface layer to close to 0 kV by performing the operation at a temperature in the range of 15 to 40 DEG C and a humidity condition of 25 to 45%, thereby effectively controlling the dry hollow fiber membrane filling rate .

In addition, the present invention can provide a water treatment module including the above-described dry hollow fiber membrane. As one example of the water treatment module,

A hollow fiber membrane module including a dry hollow fiber membrane;

A housing into which the hollow fiber membrane module is inserted;

An inlet formed at one side of the housing and through which the treated water flows; And

A water treatment module formed on one side of the housing and including an outlet through which the filtered water is discharged.

For example, the hollow fiber membrane module includes a potting portion for fixing one end or both ends of the hollow fiber membrane module; And a housing cap disposed on one side or both sides of the housing and having at least one of an inlet and an outlet. Specifically, the housing cap may be formed with a pipe coupling portion to which the fluid connection pipe is coupled. In addition, the fluid connection pipe is not particularly limited and may include, for example, at least one of a water supply target water supply line, an air injection line, a purified water discharge line, and a concentrated water discharge line.

In the water treatment module according to the present invention, the filling rate of the dry hollow fiber membrane may be 50% or more. For example, the filling rate of the dry hollow fiber membrane may be 50-65%, 52-60%, or 53-56%. Specifically, the water treatment module is manufactured through the steps of vertically positioning the dry hollow fiber membrane and washing it in a vertical direction, thereby preventing entanglement of the hollow fiber membrane, thereby securing a maximum space in the housing, The filling rate of the dry hollow fiber membrane can be increased.

In addition, when the water treatment module is subjected to dry hollow fiber membrane breakage test after filtration at a flow rate of 100 LMH for 12 hours, the breaking rate may be less than 0.1%. The breakage inspection can be carried out visually. Specifically, by maintaining the impurities remaining in the dry hollow fiber membrane at a low level, the rupture rate can be maintained within the above-mentioned range, thereby providing a water treatment module with a minimum percentage of defective parts.

Specifically, a method of manufacturing a water treatment module may include a method of forming a hollow fiber membrane module in a structure in which a plurality of the dry hollow fiber membranes that are washed, dried, and conditioned are accommodated in a cylindrical housing having a plurality of holes on a wall surface . Then, the dry hollow fiber membranes can be fixed to the inside of the housing by the potting material with both upper and lower ends thereof opened. Then, a water treatment module can be manufactured by forming a housing cap including an inlet and an outlet respectively on both sides of the housing.

At this time, the hollow fiber membrane module can form a potting part by potting the gap between the dry hollow fiber membranes at the ends of the plurality of hollow fiber membranes with a polyurethane composition, then curing the composition to seal the gap between the dry hollow fiber membranes have.

The potting portion forming step may be performed under a humidity condition of 40% or less. Specifically, the humidity condition may be 20 to 40% or 30 to 40%. By forming the potting portion in the humidity condition within the above range, it is possible to prevent the bubbling of the potting portion, thereby improving the durability of the water treatment module and prolonging the life of the module.

For example, the average distance between the dry hollow fiber membranes is preferably 0.01 to 50 mm, but is not limited thereto. That is, the dry hollow fiber membrane should be densely arranged as much as possible. However, if the inter-membrane gap is narrowed to 0.01 mm or less in order to satisfy this requirement, intermembrane occlusion tends to occur because the flow of raw water and air is difficult between the hollow fiber membranes. Also, if the interval between the membranes is increased to 50 mm or more, the filling rate of the dry hollow fiber membrane of the module is lowered and the water treatment ability is lowered.

The water treatment module includes a housing, a hollow fiber membrane module disposed in the housing, and a potting part for bonding and fixing one end or both ends of the hollow fiber membrane module. The water treatment module further includes an upper collector and a lower collector formed at upper and lower portions of the housing, An air diffuser for removing contaminants accumulated on the surface, and the like. As one example, in the filtration process in the hollow fiber membrane module, the raw water is filtered from the outside of the hollow fiber membrane by the external pressure, and the filtered treated water is collected into the upper or lower collector along the inside of the hollow fiber membrane The filtration action to be discharged to the post-treatment process can be performed.

Hereinafter, the present invention will be described in detail by way of Examples and the like according to the present invention, but the scope of the present invention is not limited thereto.

Example  1 to 2 and Comparative Example  1 to 3: Production of hollow fiber membrane

1) Hollow fiber desiccation

A spinning stock solution containing a matrix resin and an inner coagulating solution were prepared by the compositions shown in Table 1 below, and a hollow fiber membrane was spun. At this time, the contents of PES, PVP, PEG, Nonspecific and DMAc in Table 1 are shown in terms of parts by weight.

ingredient content Spinning liquid Polyisocyanurate (PES) 20 Polyvinylpyrrolidone (PVP) 5 Polyethylene glycol (PEG) 19 Expense 6 (water) Dimethylacetamide (DMAc) 50 PEG Molecular Weight (MW) 600 Viscosity (cpa) 24,000 Internal coagulation amount DMAc / water content (parts by weight) 80/20

As shown in Table 1, it was confirmed that the prepared spinning liquid maintained a viscosity ranging from 20,000 to 24,000 cps. Thereafter, the prepared spinning solution and inner coagulating solution were spinned with a double nozzle under the following spinning conditions to prepare a hollow fiber membrane.

· Spinning temperature of spinning liquid: 25 ℃

· Radiation temperature of internal coagulating liquid: 50 ℃

· Temperature of coagulation bath: 50 ℃

· Coagulation time: 5 minutes

· Radial speed: 20 m / min

2) Washing, drying and conditioning treatment

The spun hollow fiber membrane was washed, dried and conditioned. At this time, the washing, drying and conditioning conditions are shown in Table 2 below.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Suesse level 70 ° C / 12h 70 ° C / 12h 70 ° C / 12h 70 ° C / 12h 70 ° C / 12h Perpendicular 70 ° C / 5 min
25 ° C / 10 min 70 ° C / 5 min
25 ° C / 10 min 70 ° C / 5 min
25 ° C / 10 min 70 ° C / 5 min
25 ° C / 10 min 70 ° C / 5 min
25 ° C / 10 min dry At room temperature (25 ° C) ○ ○ ○ ○ ○ High temperature (70 ℃) ○ ○ ○ ○ × Conditioning Temperature 25 ℃ 25 ℃ × 25 ℃ 25 ℃ Humidity 40% 30% × 50% 40% time 2h 2h × 2h 2h

Experimental Example : Measurement of physical properties

The moisture content and the electrostatic voltage of the hollow fiber membranes washed, dried and conditioned in Examples 1 to 2 and Comparative Examples 1 to 3 were measured. The measurement conditions are described below, and the results are shown in Table 3 below.

In addition, the hollow fiber membranes prepared in Examples 1 to 2 and Comparative Examples 1 to 3 were accommodated in a cylindrical housing having a plurality of holes on a wall surface to form a hollow fiber membrane module. Both ends of the hollow fiber membranes were then potted using polyurethane. Then, a housing cap including an inlet port and an outlet port was formed on both sides of the housing to manufacture a water treatment module.

Then, the hollow fiber membrane filling rate and bubble occurrence in the pot part were visually confirmed for the manufactured water treatment module, and the results are shown in Table 4 below.

1) Moisture content (%)

As described above for each of the hollow fiber membranes, the water content was calculated by the Karl Fischer method using the following equations (1) and (2).

[Equation 1]

Water content (mg) = Reagent consumption (ml) × Reagent titer (mg / ml)

&Quot; (2) "

Water content (%) = [Water content (mg) / Tissue (mg)] × 100

2) Electrostatic voltage ( kV )

The electrostatic voltage of the hollow fiber membrane surface layer was measured for each hollow fiber membrane using an electrostatic potential measuring device (Statiron-DZ ₃ ).

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Moisture content (%) 1.7 1.4 0.7 3.5 4.3 Electrostatic voltage (kV) 0 0.2 3.1 0 0

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Filling rate (%) 55 54 40 55 55 Bubble occurrence × × × ○ ○

Referring to Tables 3 and 4, in Comparative Example 1 in which the conditioning step was not performed, static electricity was excessively generated at a moisture content of less than 1%, and Comparative Example 2 in which the conditioning humidity condition was at least 45% It was confirmed that air bubbles were generated when ported. In Comparative Example 3 where the drying step at a temperature of 70 ° C was not performed, the conditioning step was performed, but it was confirmed that air bubbles were generated when the moisture content was 4% or more.

In contrast, in Examples 1 and 2 prepared by the production method according to the present invention, the water content was controlled to 1 to 3%, and the electrostatic voltage was hardly generated in the range of 0 to 0.2 kV, , And it was confirmed that the packing ratio was 55% at maximum.

Specifically, the presence or absence of bubbles in Comparative Example 2 can be confirmed by referring to FIG. 1, it can be seen that a large amount of air bubbles are generated in the port portion of the water treatment module according to Comparative Example 2. FIG.

Claims (11)

A hollow structure having an outer surface layer and an inner surface layer,
A dry-type hollow fiber membrane in which the electrostatic voltage of the surface layer is 3 kV or less.
The method according to claim 1,
A dry hollow fiber membrane having a moisture content of 1 to 3% as measured by the Karl Fischer method.
The method according to claim 1,
The dry hollow fiber membrane has a water permeability to ultrapure water of 1000 to 5000 LMH under KS K 3100 condition.
The method according to claim 1,
The dry hollow fiber membrane comprises at least one member selected from the group consisting of polysulfone, polyethersulfone, and polyvinylidene fluoride.
Radiating a hollow fiber membrane;
Washing the radiated hollow fiber membrane;
Drying the washed hollow fiber membrane; And
And conditioning the dried hollow fiber membrane,
Wherein the conditioning step is performed at a temperature in the range of 15 to 40 DEG C and a humidity condition of 25 to 45%
A method for producing a dry hollow fiber membrane having a moisture content of 1 to 3% as measured by Karl Fischer method of the hollow fiber membrane produced.
6. The method of claim 5,
The step of washing the radiated hollow fiber membrane comprises:
A horizontal flushing step of flushing the dry hollow fiber membrane using a washing water in a state where an angle formed between the longitudinal axis of the dry hollow fiber membrane and the ground surface is 30 ° or less; And
Wherein the dry hollow fiber membrane is flush with water using a rinsing water while the longitudinal axis of the dry hollow fiber membrane is positioned at an angle of 45 DEG or more with respect to the surface of the hollow fiber membrane.
6. The method of claim 5,
The step of drying the washed hollow fiber membrane comprises:
A normal-temperature drying step of drying at a room temperature ranging from 15 to 40 캜; And
And drying at a high temperature in the range of 50 to 90 占 폚.
A hollow fiber membrane module comprising a dry hollow fiber membrane according to any one of claims 1 to 4;
A housing into which the hollow fiber membrane module is inserted;
An inlet formed at one side of the housing and through which the treated water flows; And
And an outlet formed at one side of the housing and through which filtered water is discharged.
9. The method of claim 8,
The water treatment module,
And a potting portion for fixing one end or both ends of the hollow fiber membrane module;
And a housing cap located at one side or both sides of the housing and having at least one of an inlet and an outlet.
9. The method of claim 8,
Water treatment module with 50% or more fill rate of dry hollow fiber membrane.
9. The method of claim 8,
A water treatment module with a breakage rate of less than 0.1% when dry hollow fiber membrane breakage test was performed after filtration at a flow rate of 100 LMH for 12 hours.

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